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Uzbekistan Tashkent
Year
2021
Volume
31
Issue
4
Pages
519-535
>>
Section Mathematics
Title Structure of singular sets of some classes of subharmonic functions
Author(-s) Abdullaev B.I.a, Imomkulov S.A.b, Sharipov R.A.a
Affiliations Urgench State Universitya, Institute of Mathematics, National Academy of Sciences of Uzbekistanb
Abstract In this paper, we survey the recent results on removable singular sets for the classes of $m$-subharmonic ($m-sh$) and strongly $m$-subharmonic ($sh_m$), as well as $\alpha$-subharmonic functions, which are applied to study the singular sets of $sh_{m}$ functions. In particular, for strongly $m$-subharmonic functions from the class $L_{loc}^{p}$, it is proved that a set is a removable singular set if it has zero $C_{q,s}$-capacity. The proof of this statement is based on the fact that the space of basic functions, supported on the set $D\backslash E$, is dense in the space of test functions defined in the set $D$ on the $L_{q}^{s}$-norm. Similar results in the case of classical (sub)harmonic functions were studied in the works by L. Carleson, E. Dolzhenko, M. Blanchet, S. Gardiner, J. Riihentaus, V. Shapiro, A. Sadullaev and Zh. Yarmetov, B. Abdullaev and S. Imomkulov.
Keywords subharmonic functions, $m$-subharmonic functions, strongly $m$-subharmonic functions, $\alpha$-subharmonic functions, Borel measure, $C_{q,s}$-capacity, polar set
UDC 517.559, 517.57
MSC 32U30, 31C05
DOI 10.35634/vm210401
Received 14 July 2021
Language Russian
Citation Abdullaev B.I., Imomkulov S.A., Sharipov R.A. Structure of singular sets of some classes of subharmonic functions, Vestnik Udmurtskogo Universiteta. Matematika. Mekhanika. Komp'yuternye Nauki, 2021, vol. 31, issue 4, pp. 519-535.
References
  1. Abdullaev B.I. $m-wsh$ functions, Doklady Akademii Nauk Respubliki Uzbekistan, 2012, no. 5, pp. 15-18 (in Russian).
  2. Abdullaev B.I., Imomkulov S.A. Removable singularities of subharmonic functions in the level $L_{p}$ and $L_{p}$$1$ , Uzbekskii Matematicheskii Zhurnal, 1997, no. 4, pp. 10-14 (in Russian). https://zbmath.org/?q=an:0921.31002
  3. Abdullaev B.I., Yarmetov Zh.R. On singular sets of subsolutions of elliptic operators, Vestnik Krasnoyarskogo Gosudarstvennogo Universiteta, 2006, no. 9, pp. 74-80 (in Russian).
  4. Vaisova M.D. Potential theory in the class of $\alpha$-subharmonic functions, Uzbek Mathematical Journal, 2016, vol. 3, pp. 46-52 (in Russian).
  5. Vitushkin A.G. A set of positive length having a zero analytic capacity, Doklady Akademii Nauk SSSR, 1959, vol. 127, pp. 246-249 (in Russian). https://zbmath.org/?q=an:0087.07103
  6. Dolzhenko E.P. On the representation of continuous harmonic functions in the form of potentials, Izvestiya Akademii Nauk SSSR. Ser. Matematicheskaya, 1964, vol. 28, issue 5, pp. 1113-1130 (in Russian). http://mi.mathnet.ru/eng/izv3043
  7. Dolzhenko E.P. On the singularities of continuous harmonic functions, Izvestiya Akademii Nauk SSSR. Ser. Matematicheskaya, 1964, vol. 28, issue 6, pp. 1251-1270. http://mi.mathnet.ru/eng/izv3053
  8. Maz'ya V.G. Classes of sets and measures connected with embedding theorems, Embedding theorems and their applications, Moscow: Nauka, 1970, pp. 142-159.
  9. Maz'ya V.G., Khavin V.P. Non-linear potential theory, Russian Mathematical Surveys, 1972, vol. 27, issue 6, pp. 71-148. https://doi.org/10.1070/RM1972v027n06ABEH001393
  10. Maz'ja V.G. On $(p,l)$-capacity, embedding theorems, and the spectrum of a selfadjoint elliptic operator, Mathematics of the USSR-Izvestiya, 1973, vol. 7, issue 2, pp. 357-387. https://doi.org/10.1070/IM1973v007n02ABEH001942
  11. Mel'nikov M.S., Sinanyan S.O. Aspects of approximation theory for functions of one complex variable, Journal of Soviet Mathematics, 1976, vol. 5, issue 5, pp. 688-752. https://doi.org/10.1007/BF01091909
  12. Pokrovskii A.V. Removable singularities of solutions of non-linear elliptic equations, Russian Mathematical Surveys, 2007, vol. 62, issue 3, pp. 629-630. https://doi.org/10.1070/RM2007v062n03ABEH004422
  13. Sadullaev A., Abdullaev B. Potential theory in the class of $m$-subharmonic functions, Proceedings of the Steklov Institute of Mathematics, 2012, vol. 279, issue 1, pp. 155-180. https://doi.org/10.1134/S0081543812080111
  14. Sadullaev A. Rational approximation and pluripolar sets, Mathematics of the USSR-Sbornik, 1984, vol. 47, no. 1, pp. 91-113. https://doi.org/10.1070/SM1984v047n01ABEH002632
  15. Sadullaev A.S., Yarmetov Zh.R. Removable singularities of plurisubharmonic functions of class $Lip_{\alpha}$, Sbornik: Mathematics, 1995, vol. 186, no. 1, pp. 133-150. http://doi.org/10.1070/SM1995v186n01ABEH000008
  16. Sadullaev A.S., Abdullaev B. A removable singularity of the bounded above $m-wsh$ functions, Doklady Akademii Nauk Respubliki Uzbekistan, 2015, no. 5, pp. 12-14 (in Russian).
  17. Sadullaev A.S., Abdullaev B.I. Removable singularity $m-wsh$ functions of the class $Lip_{\alpha}$, Vestnik NUUz, 2015, no. 1, pp. 4-6 (in Russian).
  18. Sadullaev A.S., Abdullaev B.I., Sharipov R.A. A removable singularity of the bounded above $m-sh$ functions, Uzbek Mathematical Journal, 2016, no. 3, pp. 118-124 (in Russian).
  19. Khusanov Z.Kh. Capacity properties of $q$-subharmonic functions. I, Izvestiya Akademii Nauk UzSSR. Ser. Fiz.-Mat. Nauk, 1990, no. 1, pp. 41-45 (in Russian). https://zbmath.org/?q=an:0709.31006
  20. Khusanov Z.Kh. Capacity properties of $q$-subharmonic functions. II, Izvestiya Akademii Nauk UzSSR. Ser. Fiz.-Mat. Nauk, 1990, no. 5, pp. 28-33 (in Russian). https://zbmath.org/?q=an:0729.31010
  21. Chirka E.M. Removable singularities of holomorphic functions, Sbornik: Mathematics, 2016, vol. 207, no. 9, pp. 1335-1343. https://doi.org/10.1070/SM8665
  22. Chirka E.M. On removable singularities of complex analytic sets, Sbornik: Mathematics, 2017, vol. 208, no. 7, pp. 1073-1086. https://doi.org/10.1070/SM8756
  23. Abdullaev B.I. Subharmonic functions on complex hyperplanes of ${\mathbb C}$${n}$ , Journal of Siberian Federal University. Mathematics and Physics, 2013, vol. 6, issue 4, pp. 409-416. http://mi.mathnet.ru/eng/jsfu326
  24. Abdullaev B.I., Imomkulov S.A., Sharipov R.A. Removable singular sets of $m$-subharmonic functions, Algebra, Complex Analysis, and Pluripotential Theory, Cham: Springer, 2018, pp. 1-11. https://doi.org/10.1007/978-3-030-01144-4_1
  25. Karim S.A.A., Nguyen V.T. On the space of $m$-subharmonic functions, Theoretical, Modelling and Numerical Simulations Toward Industry 4.0, Singapore: Springer, 2020, pp. 133-166. https://doi.org/10.1007/978-981-15-8987-4_9
  26. Åhag P., Czyż R., Hed L. Extension and approximation of $m$-subharmonic functions, Complex Variables and Elliptic Equations, 2018, vol. 63, issue 6, pp. 783-801. https://doi.org/10.1080/17476933.2017.1345888
  27. Åhag P., Czyż R., Hed L. The geometry of $m$-hyperconvex domains, The Journal of Geometric Analysis, 2018, vol. 28, issue 3, pp. 3196-3222. https://doi.org/10.1007/s12220-017-9957-2
  28. Åhag P., Czyż R. On a characterization of $m$-subharmonic functions with weak singularities, Annales Polonici Mathematici, 2019, vol. 123, pp. 21-29. https://doi.org/10.4064/ap180628-10-9
  29. Blocki Z. Weak solutions to the complex Hessian equation, Annales de l'institut Fourier, 2005, vol. 55, no. 5, pp. 1735-1756. https://doi.org/10.5802/aif.2137
  30. Blanchet P. On removable singularities of subharmonic and plurisubharmonic functions, Complex Variables, 1995, vol. 26, issue 4, pp. 311-322. https://doi.org/10.1080/17476939508814792
  31. Cegrell U. Sur les ensembles singuliers impropes des plurisubharmonic, Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences, Sér. A, 1975, vol. 281, pp. 905-908 (in French). https://zbmath.org/?q=an:0313.32023
  32. Chirka E.M. On the removal of subharmonic singularities of plurisubharmonic functions, Annales Polonici Mathematici, 2003, vol. 80, pp. 113-116. https://doi.org/10.4064/ap80-0-8
  33. Ching J., Cîrstea F. Existence and classification of singular solutions to nonlinear elliptic equations with a gradient term, Analysis and PDE, 2015, vol. 8, no. 8, pp. 1931-1962. http://doi.org/10.2140/apde.2015.8.1931
  34. Dinew S., Kolodziej S. A priori estimates for the complex Hessian equation, Analysis and PDE, 2014, vol. 7, no. 1, pp. 227-244. https://doi.org/10.2140/apde.2014.7.227
  35. Gardiner S.J. Removable singularities for subharmonic functions, Pacific Journal of Mathematics, 1991, vol. 147, issue 1, pp. 71-80. https://zbmath.org/?q=an:0663.31004
  36. Lelong P. Ensembles singuliers impropres des fonctions plurisousharmoniques, Journal de Mathématiques Pures et Appliquées. Neuvième Série, 1957, vol. 36, pp. 263-303 (in French). https://zbmath.org/?q=an:0122.31902
  37. Li S.-Yi. On the Dirichlet problems for symmetric function equations of the eigenvalues of the complex Hessian, The Asian Journal of Mathematics, 2004, vol. 8, no. 1, pp. 87-106. https://zbmath.org/?q=an:1068.32024
  38. Lu H.C. Solutions to degenerate Hessian equations, Journal de Mathématiques Pures et Appliquées, 2013, vol. 100, issue 6, pp. 785-805. https://doi.org/10.1016/j.matpur.2013.03.002
  39. Lu H.C. A variational approach to complex Hessian equations in $\mathbb C$$n$ , Journal of Mathematical Analysis and Applications, 2015, vol. 431, issue 1, pp. 228-259. https://doi.org/10.1016/j.jmaa.2015.05.067
  40. Lu H.C., Nguyen V.-D. Degenerate complex Hessian equations on compact Kähler manifolds, Indiana University Mathematics Journal, 2015, vol. 64, issue 6, pp. 1721-1745. https://www.jstor.org/stable/26316203
  41. Marcus M., Veron L. Removable singularities and boundary traces, Journal de Mathématiques Pures et Appliquées, 2001, vol. 80, issue 9, pp. 879-900. https://doi.org/10.1016/S0021-7824(01)01209-0
  42. Mattila P. Integralgeometric properties of capacities, Transactions of the American Mathematical Society, 1981, vol. 266, no. 2, pp. 539-554. https://doi.org/10.2307/1998439
  43. Mattila P. A class of sets with positive length and zero analytic capacity, Annales Academiae Scientiarum Fennicae Series A. I. Mathematica, 1985, vol. 10, pp. 387-395. https://doi.org/10.5186/aasfm.1985.1043
  44. Nguyen X.U. Removable sets of analytic functions satisfying a Lipschitz condition, Arkiv för Matematik, 1979, vol. 17, no. 1-2, pp. 19-27. https://doi.org/10.1007/BF02385454
  45. Nguyen X.U. A removable set for Lipschitz harmonic functions, Michigan Mathematical Journal, 1990, vol. 37, issue 1, pp.45-51. https://doi.org/10.1307/mmj/1029004065
  46. Nguyen N.C. Hölder continuous solutions to complex Hessian equations, Potential Analysis, 2014, vol. 41, issue 3, pp. 887-902. https://doi.org/10.1007/s11118-014-9398-5
  47. Nguyen N.C. Subsolution theorem for the complex Hessian equation, Universitatis Iagellonicae Acta Mathematica, 2012, no. 50, pp. 69-88.
  48. Nguyen V.T. The convexity of radially symmetric $m$-subharmonic functions, Complex Variables and Elliptic Equations, 2018, vol. 63, issue 10, pp. 1396-1407. https://doi.org/10.1080/17476933.2017.1373347
  49. Nguyen V.T. On delta $m$-subharmonic functions, Annales Polonici Mathematici, 2016, vol. 118, pp. 25-49. http://doi.org/10.4064/ap3959-9-2916
  50. Riihentaus J. Exceptional sets for subharmonic functions, Journal of Basic and Applied Sciences, 2015, vol. 11, pp. 567-571. http://doi.org/10.6000/1927-5129.2015.11.75
  51. Riihentaus J. Removability results for subharmonic functions, for harmonic functions and for holomorphic functions, Matematychni Studii, 2016, vol. 46, issue 2, pp. 152-158. http://doi.org/10.15330/ms.46.2.152-158
  52. Riihentaus J. A removability results for holomorphic functions of several complex variables, Journal of Basic and Applied Sciences, 2016, vol. 12, pp. 50-52. http://doi.org/10.6000/1927-5129.2016.12.07
  53. Kaufman R., Wu J.-M. Removable singularities for analytic or subharmonic functions, Arkiv för Matematik, 1980, vol. 18, issue 1-2, pp. 107-116. https://doi.org/10.1007/BF02384684
  54. Shapiro V.L. Subharmonic functions and Hausdorff measure, Journal of Differential Equations, 1978, vol. 27, issue 1, pp. 28-45. https://doi.org/10.1016/0022-0396(78)90111-0
  55. Verbitsky M. Plurisubharmonic functions in calibrated geometry and $q$-convexity, Mathematische Zeitschrift, 2010, vol. 264, issue 4, pp. 939-957. https://doi.org/10.1007/s00209-009-0498-7
  56. Carleson L. Selected problems on exceptional sets, Princeton: D. Van Nostrand Company, 1967. https://zbmath.org/?q=an:0189.10903
  57. Chirka E.M. Kompleksnye analiticheskie mnozhestva (Complex analytic sets), Moscow: Nauka, 1985.
  58. Shabat B.V. Vvedenie v kompleksnyi analiz. Chast' 2 (Introduction to complex analysis. Part 2), Moscow: Nauka, 1985.
  59. Joyce D. Riemannian holonomy groups and calibrated geometry, Berlin, Heidelberg: Springer, 2003. https://doi.org/10.1007/978-3-642-19004-9_1
  60. Riihentaus J. Subharmonic functions, generalizations, holomorphic functions, meromorphic functions, and properties, Bentham Science Publishers, 2021. https://doi.org/10.2174/97898114987011210101
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